Significance Identifying the source and dynamics of persistent HIV-1 during combinational antiretroviral therapy (cART) is crucial for understanding the barriers to curing HIV infection. Through genetic characterization of HIV-1 DNA in infected cells from peripheral blood and gut-associated lymphoid tissue from patients after long-term suppressive cART, our study reveals that the primary barrier to a cure is a remarkably stable pool of infected memory CD4 + T cells. Through in-depth phylogenetic analyses, we determined that the HIV-1 reservoir in these cells from eight patients is kept stable during long-term cART and, with little evidence of viral replication, this population could be maintained by homeostatic cell proliferation or other processes.

Memory T cells maintained a relatively constant HIV-1 DNA integrant pool that was genetically stable during long-term effective ART. These integrants appear to be maintained by cellular proliferation and longevity of infected cells, rather than by ongoing viral replication.

We examined the association between amphetamine use and HIV incidence for 2991 men who have sex with men (MSM) who tested anonymously for HIV in San Francisco. HIV incidence among 290 amphetamine users was 6.3% per year (95% CI 1.9-10.6%), compared with 2.1% per year (95% CI 1.3-2.9%) among 2701 non-users (RR 3.0, 95% CI 1.4-6.5). HIV prevention programmes in San Francisco should include efforts to reduce amphetamine use and associated high-risk sexual behaviors.

Both interventions were effective in reducing high-risk sexual behavior among MSM repeat testers. PCC participants demonstrated significant behavioral change more swiftly and reported a more satisfying counseling experience than UC participants.